Uh.....should not it have been a 40 Flap landing ?!?!

It takes at least 30 seconds (closer to 35) to retract B738 flaps from 30 to up. That is with two engines at idle, two engine driven hydraulic pumps, two electric hydraulic pumps and an intact aircraft.

I guess all will be revealed.

Properly configured for 30 flap
 

Dc-Ate, I agree that 40 flap would be my choice, but both 30 and 40 flap settings can accomplish the job safely with out any fuss. The point here was focused on earlier speculation about whether the were extended at all and the adjective "properly" configured was an attempt to convey that the aircraft flaps and slats were in a landing configuration at touch down as opposed to retracted at touched down or even extended for touch down then hurridely retracted for all types of posted theories.

It is highly unlikely that the last error, or indeed the last few errors in the chain, weren't made by the pilots. The real improvements will be in identifying why these errors were made. ie did a poor culture exist within the pilot group with respect to briefing intentions should the landing not be working out? Was the authority gradient in the flightdeck appropriate? Was deviation from SOPs the norm? Do the SOP's preclude retracting flap while still on an active runway? Does the rostering system result in fatigue? Were the pilots likely to face negative feedback from management if they diverted or conducted a go-around? The answers to questions like that will describe to you 100% correct in my opinion.
Senior airline management need to be responsible for the cultivation of a culture in which this is the norm and deviating from it is seen as poor airmanship.

IMO this is going to be a major factor in the findings. Again....how can a companies SOP's be approved when they are flawed in this way? This incident may be the result of decisions made at a management level, should the regulator take some responsibility ? The head of operations?

And you know this how? Are you sure it wasn't 8 times normal tension? How did you calibrate the tensiometer?

My Lord.....I sincerely hope that you are not an airline pilot. If that was the case, the Captain should surely be held responsible for making the decision to continue the approach with a flap problem into a short strip while 'confused'.

Who would have thought? Instead of it being some freakish anomaly with flaps retracting by themselves , it's looking like a case of poor flight discipline. Who is responsible for the safety culture of an airline? I have my ideas on the answer to that.

Won't work very well in a 737-800 but anyway, if the SOP's don't stipulate where the after landing proceedure is to be commenced then there is a hole in the cheese just waiting to bite a crew.
Your friend is wrong.

There are some posts on this thread that scare me a bit if they are made by airline pilots. Hopefully they are just teenage kids who love Microsoft FS and enjoy pretending to know things on this forum.
At the end of the day a combination of solid SOP's and the flight discipline to follow them and this over run would never have ocurred.
Framer

once the a/c is on ground with reversers deployed,there is no question of trying to get airborne again.look what happened to AI Express at Mangalore.
I s there any talk about where the a/c touched down in this case?

Flaps 30 is good enough for a 7000ft rwy...its good enough for 6000ft even if its wet with good braking action....no sweat.

The only 'fly in the ointment' for Dingy737 (#162) is that (OK, it did come from the WSJ, that fount of all that is knowledgeable and right) the flap lever was reportedly found in the up detent in the wreckage. That certainly is one heck of an 'up selection to the actuator':rolleyes:

BOAC. The flap handle was found in a landing flap detent.

CG

Thanks CG - that makes more sense. WSJ starring again in reporting! Link to WSJ in post #138 was my source.

Finding the flap handle in the landing detent is inconclusive. If they ran the evacuation checklist the flaps would have been placed in the flap 40 detent. We will know soon enough where the flaps were or were not during the roll out. Speculation at this time is only that, speculation.

Jet

Here is an example of a landing which should have been aborted. Note the application of flaps deep into the flare!

The Aerogal video in youtube shows normal landing with landing flaps maybe 30 to 40 in the last seconds. Title of video is misleading too - nothing scary about it.

On the -200 we used to extend flaps from 30 to 40 after landing sometimes to help with the drag. Felt effective. I had never heard of retracting flaps while on landing roll until pprune...

Really? I counted about a 12 second float, during which he added more flaps. Now THAT, I have never heard of. You really should not change configuration so close to the ground like that.

You never did your PPL? I thought it was standard to retract flaps on a short field landing in a small aircraft. I would not advise to get in the habit of doing this in an airliner though.

Sorry cannot quote. Scary is relative. If you want scary extend the speedbrakes a few degrees to stop the float (not recommended). Of course I am certain nobody has done this, or landed with the flap load relief operating. These things never happen to us, only others far far away.

PPL? Too old to remember, however I seem to remember a discussion about instead of retracting the flaps after landing some people retracted the gear instead. Maybe that was the reason they didn't teach that.

"On the -200 we used to extend flaps from 30 to 40 after landing sometimes to help with the drag. Felt effective."

No where to find in the Boeing 737-200 FCOM or FCTM.

Time for a serious talk with the chief-pilot.....:=

Landed with the flap load relief operating? Mucked around with flap below 500 feet or on the runway? Geez no wonder you guys used to stack em more often in the old days. Never ever seen it or heard of it happening in the decade or so I've been with airlines. We would have gone around at 500ft if we were at the load relief speed. Things change a bit over the years by the looks.

gotofly -

Is there any talk about where the a/c touched down in this case?

Flaps 30 is good enough for a 7000ft rwy...its good enough for 6000ft even if its wet with good braking action....no sweat.
-----------------------------------------------------------------------

Non pilot eyewitnesses reported a long landing.

My perfromance charts say, even with Flaps 40, that 6000' will have weight restrictions if wet.

1500 hrs in the 737NG, most guys use 7000', or perhaps slightly, more runway, as the switch from Flaps 30 to Flaps 40.Wet runway and the switch is made for longer runways. Landing distance is part of the decision, the more critical factor is the reduced tendency to float with Flaps 40.

ref Aerogal
 

If I had to guess: flaps selected, but not extended because of flap load relief. When just before touch, speed bled off, flaps extended (just speculation).
BTW do they use FCOM's in South America?:}

I guess that would depend on the braking that was used considering that at Flap 30 and MLW Auto brake 2 will pull you up in 2370m nil wind. The runway is shorter than that so AB2 is obviously out if you're silly enough to be using Flap 30. Try AB3 Flap 30, if you do everything perfectly as by the book with nil wind it will pull you up 370m short of the end. How many people chew up 370m by carrying speed into the flare or having a touchdown located further in than 1000 foot? Plenty. If you were AB3 and flap 30 and touched down at the 2000ft markers for whatever reason, you will have to intervene with some heavy braking to avoid an overrun.
What if it was a 3 kt tail instead of nil wind? That increases all the distances by about 100m. Nah, Flap 30 in this situation would be a poor choice if you had no wind and were heavy.
Even Flap 40 AB2 will stop you only 30m short of the grass at MLW and put you 70m off the end if you have a 3kt tailwind.
My point? This needed to be a Flap 40 landing with AB3 as a minimum which will stop the aircraft in 1700m if everything goes well, it leaves you with about 500m for unforseen things like
1/ not crossing the threshold at exactly 50'
2/ not being exactly on speed
3/ not executing the perfect flare and touchdown
4/ the reported nil wind actually being a slight tailwind.
For all I know this crew did use Flap 40 and appropriate braking, but to say that Flap 30 is 'no sweat' is to ignore variables that you have limited control over, and to bank on everything going as planned.

PS all the above figures are derived from my books and the aircraft they apply to have 'short field performance'. I don't know if the accident aircraft did as well.
At max landing weight the aircraft legally requires a strip length of 1620m dry or 1860m wet (nil wind, standard day etc). If it's not short field performance then it'l need a fraction more.

Emergency return
 

Question: If you depart from a 7400 ft runway at max Landing weight and loose an engine in a 737-800 can you return to land at that field.
The VREF speeds for max landing weight are aprox.,
Flaps 40= 142. Faps 30= 150 Flaps 15 = 158
The Boeing procedure for a single engine landing is to use flap 15. The Boeing Advisory landing distance for flap 15 one eng. inop. on a wet runway= 4888 feet, using max manual braking and max operative reverse thrust and of course touching down at the 1000 foot point.
I know of 2 such return to land events at that field at flaps 15 eng. out, still with no fuss, so flaps 30 is still more than adequate, and 40 being the best choice. So using flaps 30 are not to blame here.
Also the Boeing after landing procedure kicks in when clear of the runway which is when the flaps would be retracted, after speaking with a colleague at this airline in question this is also their SOP.
I do not understand this procedure of retracting flaps on the landing roll as they will transistion from the gratest drag posistion to the greatest lift posistion on its way to a fully stowed posistion and adversely affect the weight on wheels for proper braking.

The rest of your post makes sense to me but the above quoted text doesn't.

While full flaps produces more drag, more lift per unit of airspeed is produced as well. Note the lower Vref speeds associated with increased flaps setting. On jet transports, ground spoilers increase the weight on wheels and produce additional drag. This is far more effective at dumping lift than retracting flaps and adds drag instead of reducing it.

Retraction of flaps during the landing roll reduces the amount of lift produced at any given airspeed, thus increasing weight on wheels. It is an accepted and even manufacturer recommended technique to reduce landing roll distance on some light aircraft. Especially handy in bush flying.

I'm not aware of any jet transport aircraft where flap retraction during the landing roll is a recommended or approved action though. Ground spoilers are far more effective anyway and the danger of inadvertently selecting gear up instead of flaps up is mostly eliminated.

The objective on normal concrete or tarmac runways is to have the flaps stowed before turning onto a narrow taxiway where the engines may overhang the edges and foreign objects may be blown up, damaging the flaps. This is done late in the landing run at fairly low speed where any lift or drag considerations are minimal. Only a problem where taxiways are narrow and poorly laid out and more of a problem for turboprops than for jets.

Foreign object damage to flaps is a big problem at unmade airstrips where jets are unlikely to operate and pilots experienced in these conditions will have devoloped a habit of getting the flaps up as soon as reasonably practical to minimise the risk of damage.

Yes you can. In a perfect situation you will have plenty of room assuming max manual braking (about 1250m to stop from memory) but I think you already know that.

Depending on the braking scheduled IMO.
The s/e example is an emergency situation and therefore no factoring is required (as I am sure you know) .
Basically, by choosing Flap 30 (and I'm not saying this crew did), unless you select autobrake max your buffer for speed maintenance, threshold crossing height, touchdown point, float in the flare, tailwind etc is only 370m. Not enough in my opinion when simply selecting Flap 40 brings you an extra 200m of buffer. Of course it can be done at flap 30, but why would you?
If you applied max braking you could stop in 1000m....but why would you?
stack the deck in your favour and make sound choices, Flap 30 is not a sound choice on a runway 2200m long unless gusts are a factor IMO.

I guess we have a different definition of a 'normal concrete or tarmac runway' then.
In that scenario I would be briefing it before leaving cruise altitude and below 15kts before making the selection. But maybe that is because I have the luxury of operating into better strips and I don't understand how common it is to have taxiways like that as part of the route structure.

yet earlier a poster observed other aircraft from this carrier retracting the flaps on the runway subsequent to this accident. So is a finding going to be a culture within the pilot group to not follow SOP's? Poor safety culture? If so , I believe the only way around this is to find management level positions liable for the creating of acceptable safety cultures with pilot groups.Rather than the current situation where high level decision making degrades safety cultures.
Framer

Lift / Drag
 

Thanks Westhawk on review you are correct. I was actually thinking of an aborted takeoff where the procedure is to extend the flaps to 40 after decelerating thru 60 knots and if done to soon at higher speeds, the flaps going from a takeoff posistion of 5 to 40 would increase lift and adversely affect braking. I must start posting in the day and not at 4 am.

extending flaps further to 40 during a reject????

Who's SOP is that - its sure as heck not Boeings.


R u sure your not confusing it with the EVAC drill.


WJAP

No idea? is it something that used to be done many moons ago?
Dingy737, you also stated;
and have only joined up and posted on this particular thread, can I ask you if you are an engineer for this company or have some other sort of inside connection?
For me that would explain your in depth knowledge of the cable tension and also why you were emphatic that the crew used flap 30 very shortly the crash.
I understand if you would rather keep that information to yourself, just thought I'd ask in case you don't mind revealing how you know these things.

Rejected Takeoff
 

As I remeber it for the 737 during an abort
F/O call 60 kts decelerating
Stop assured:
Captain:Reverse thrust to idle by taxi speed.
F/o: Lowers flaps to 40 degrees
The thinking was to have the flaps in the evacuation posistion in anticipation the abort may lead to an evac. I am not uptodate wasnt aware it was changed. but i do remember some f/o's being overly anxious to complete their drill and running the flaps to 40 while still above 60 kts and yes the evacuation drill call for the F/O to select flaps to 40 which would have already been done.
I have lots of friends in the region and i am just sharing the info i consider credible, currently in the sand.

Dingy....


Sorry mate I think your confused... unless your company (which one was that) deviated from recommended boeing SOP and created your own.

The rejected takeoff drill says nothing of lowering flaps...in fact increasing flaps may even take more weight off the wheels and further inhibit braking.... as you recall at speeds less that 100kts the reverse thrust is less useful than the brakes.

The EVAC drill which is completely separate has the captain lower flaps to 40 to assist with over the wing egress..

Which model 37 are you referring to cause I've flown the classics and the NGs and neither have ever had anything your referring to.

I gotta call BS on your claim - either that or your memory is very incorrect.

WJP

Boeing procedures
 

A 737 can come with hundeds of options all dependant on the operator.
While flying as a passenger on a Delta 738 I observed the de/anti icing procedure take place with the slats and flaps set for takeoff, on competion they were retracted for taxi. I asked the Captain about it and his reply was after the merger with northwest they adopted this procedure to have conformity acrooss the merger. I know several operators that still de-ice with flaps/slats retracted. So my question is, can an operator have its own procedure as long as Boeing sactions it?
The answer would have to be yes.
And if so what then are Boeing procedures? What you know as boeing procedures may just be your operators choice of options on a boeing aircraft.

Smartcockpit
 

WJP the smartcockpit web site for B737NG-briefings displays the Ryanair RTO procedures which conflicts with yours, which require the Captain to select flaps to 40. Their procedure is to have the F/O do it.
Which is Boeings and how would you know? It is clear operators can make changes to boeings procedures. The procedure I quoted was for the F/O to run flaps to 40 when below 60 knots and stopping assured, I think the focus here is on stopping assured as in decelerating below 20 knots with 5000 feet of runway left , it was the crews call and the operators procedure not mine.

our sops as well call for F/O to
-note reject speed
-Monitor braking speed brakes and reverse
-through 60 knots select flaps 40
and depressurize the Aircraft.

These I believe are closely worded to Boeing SOPs to keep things standard
for a Boeing 738 or NG
My two cents .

llnfder what company is that may i ask.

The Boeing issued flight crew training manual for the 737-6,7,8,9 and BBJ
does not allude anywhere to the flaps being lowered during a reject...

why would you depresssurize the aircraft for a simple reject NOT leading to an evac?



Regards

WJP

RTO
 

I beleive procedures are created from lessons learnt in previous incidents. Time is of the essence in most emergencies, rather than have several different rto drills why not have one that covers the worse case, its just being proactive and erring on the safe side. The 738 pressurizes the cabin on the take off roll, for passenger comfort. The drill as i knew it did involve selecting the outflow valve to manual and holding it until open to make sure their was no pressure differential. If the abort escalated to an evac. you would be well ahead of the game, if it did not no harm caused.
I was hoping that someone could post a Boeing offical link if it exist.
As for boeing manuals all operators will have Boeing issued manuals, with boeing printed on every page, the text and procedures will differ amongst operator as we have established.

Out voted..!!
 

Looks like WJAPilot has been out voted..!!:ugh::rolleyes::=:D

@ GYS
 

Yes, we bloody do. What kind of a stupid, pointless, useless comment is that? :ugh:

The landing distance figures have been mentioned by a few people here, but I recall those are factored without the use of thrust reverser. So you would still have a slightly bigger margin in terms of distance before departing the runway, right?

No it doesn't with standard Boeing. But the FO selecting flap 40 used to be a recall item for the evacuation checklist with standard Boeing. I believe however, that different operators can have their own procedures approved which may vary greatly from the standard stuff.

I just took a look at the Smartcockit stuff. The Ryanair reject manouvre alludes the outdated procedure of the FO flap 40 recall item on the old Boeing evac checklist. It is dated 2008 when the standard SOPs changed and maybe Ryanair have also amended their procedure since then?

ryanair SOP's changed?
 

hell, they change SOP's more often than i change socks!

Ya lost all street credit when you used RYAN AIR as your example.

The drill to depressurize the cabin and lower flaps in all rejects is absurd...
but a point that will be lost by trying to argue the point.

The majority if not more than 90% of all rejects have nothing to do with requiring an evac.

But it doesn't matter either way... Ill never work for Ryan Air and won't have to worry about it.

Off to maui for the week enjoy chaps..

WJP

WJApilot I think you are the one losing street cred. making posts like your last one. Ryanair (not RYAN AIR) successfully operates around three times as many 737s as Westjet if that is who you work for. Those who have flown the 737 a bit longer remember various old procedures. Hopefully with experience SOPs are improved and we can lessen the risk of having our mistakes disected on PPRuNe including at least three recent landing accidents at night with the NG in central america / carribbean.

Caribbean Fleet Changes
 

Co-pilot reported to be 23/24 yrs old not much hours unless he has been crop-dusting from 14 which I doubt. Pilot was veteran